<link rel="stylesheet" href="${resource(dir:'css',file:'cupertino/jquery-ui-1.8.custom.css')}" />
<g:javascript src="jquery/jquery-ui-1.8.custom.min.js"/>

<script language="javascript">
    $(document).ready(function() {     
       $("#planList").submit( function () {
            if($("#classesid").val() == ""){
                alert("请选择班级")
                return false
            }
            return true;
        });
    });
 
</script>